Dinosaurs were just lizards who got too much oxygen

I've only had this explained to me a few times, so if anyone's more
familiar with this story, please correct me! Anyway, this is the way to
explain all the dinosaur bones and layers of Earth containing them:
So, once upon a time, long long ago but right here on spaceship Earth, but before the
time of Noah, lizards were really, really big and humans lived a long time.
What in the world could cause this? More oxygen, of course! You know how
the Greenhouse Effect works, right? Think like that, only with a big layer of
water surrounding the atmosphere, keeping lots of oxygen in. And that water
was perfectly fine just where it was until God got mad and let it fall --
Noah's flood! Naturally, the flood made the Earth a little muddy. Reptiles got buried in
the lowest layers of the mud because they were too dumb to find higher ground. The animals got buried
according to how far up they were able to make it before drowning, which might explain the apparent
evolution in soil layers - they're all really the same age, though.
Oh yeah, and the antediluvian atmospheric oxygen content also messed with
things like Carbon-14 content. All modern animals are
descended from the ones taken on the ark... probably all the smallest models that
were available at the time; I mean, if you drove a Ford Festiva, would you take a german shephard cross country or a miniature pomeranian?

Et voila.

(By the way, not even most of the Creationists I know would tell you this one, but it's definitely the most amusing/disturbing twisting of science I've been earnestly told. Sorry I couldn't tell it with a straight face... it's much more effective that way.)

Paleontologists have long noted the hollow bones of many dinosaurs, but did not seriously
consider these hollows to serve any other purpose than mass reduction. However, many biologists have started to
seriously entertain the notion that dinosaurian respiration was more
akin to that of birds than of mammals. In addition to the strong
fossil evidence for four-chambered hearts and respiratory air sacs,
further evidence suggests nasal turbinates to reduce respiratory
water loss (a trait largely shared by birds and mammals).

Evidence strongly suggests a
unidirectional respiratory system at least somewhat similar to that
of birds, even though researchers have not formed an adequate
hypothesis for the mechanism by which breathing took place. A
reptilian hepatic piston would be unlikely to
move adequate volumes of air through the lungs using
mammalian metabolism as a model, but a cardiopulmonary system more
reminiscent of that of birds yields better explanatory adequacy while
still allowing for the mass and/or activity levels of many families
of dinosaur.

However, ultimately this adaptation led to the demise of the dinosaurs, as it allowed them to have more mass for lung space, making them less buoyant, and causing them all to perish in the Flood.